I'm a XHTML/CSS/JAVASCRIPT developer currently learning Flex
3 to use with Java & ASP.NET for RIA.

I'm trying to see if one could embed Flex 3 applications into
an XHTML file - much like using Flash. For example, let's say if I
develop an RIA in Flex 3 - which contains a menu. Can I just
compile the menu into a SWF and call that up with the <embed>
on an XHTML page?

The reason is because the website I'm developing, I'd like to
have the static pages remain in XHTML and the RIA in Flex 3. But, I
want the menus to look consistent - so I would just embed the SWF
file.